St. Joseph, IL Weather & Growing Conditions
Overnight
66°F
Mostly Cloudy
Mostly cloudy, with a low around 66. East southeast wind around 7 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 66°F | Mostly Cloudy | 7 mph ESE | 7% |
| Saturday | 87°F | Chance Showers And Thunderstorms | 6 to 9 mph S | 36% |
| Saturday Night | 68°F | Slight Chance Showers And Thunderstorms | 7 mph S | 31% |
| Sunday | 83°F | Showers And Thunderstorms Likely | 3 to 10 mph N | 57% |
| Sunday Night | 59°F | Showers And Thunderstorms Likely | 9 to 13 mph NE | 62% |
| Monday | 69°F | Showers And Thunderstorms Likely | 14 mph NE | 68% |
| Monday Night | 54°F | Chance Showers And Thunderstorms | 10 to 15 mph NE | 49% |
| Tuesday | 67°F | Chance Showers And Thunderstorms | 13 mph NE | 31% |
| Tuesday Night | 52°F | Mostly Cloudy | 6 to 13 mph NNE | 13% |
| Wednesday | 68°F | Partly Sunny | 7 to 10 mph NNE | 4% |
| Wednesday Night | 53°F | Partly Cloudy | 3 to 9 mph NNE | 4% |
| Thursday | 71°F | Mostly Sunny | 5 to 8 mph N | 5% |
| Thursday Night | 54°F | Partly Cloudy | 6 mph NNE | 3% |
| Friday | 72°F | Mostly Sunny | 3 to 8 mph NNE | 3% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Joseph, IL
Last spring frost
Apr 20
First fall frost
Oct 21
Growing season
182 days
Hardiness zone
6a
Explore more for St. Joseph, IL: full frost dates · planting calendar · Illinois frost dates
Climate data from the nearest NOAA station, Ogden, Il (4.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.